The comp is actually "sportier," ironically. neither are really "competition" level, whatever that means. I believe the Sport has eyelets for a front rack, so if you ever want to tour, or carry larger loads, this is a major bonus. The sport will be lighter, so probably just a little more fun for riding around unloaded. I don't know if the vibration dampening properties of the carbon fork on the comp or the steel of the sport will be better, but I can tell you from experience that Jamis makes some smooth riding steel frames.
Keep in mind that you can also always upgrade components if you are so inclined.